Fabrication of an Amperometric Biosensor Based on the Immobilization of Glucose Oxidase in a Modified Molecular Sieve Matrix

Abstract

An enzyme electrode was developed, based on immobilizing glucose oxidase (GOx) on a modified molecular sieve matrix fabricated with an amperometric oxygen electrode. The large specific surface area of the molecular sieve matrix resulted in high enzyme loadings. The GOx immobilized in this manner was stable and maintained its high activity for at least 4 months. Fourier transform infrared spectra were employed to give insights into the intermolecular interactions between the molecular sieve and the enzyme. The pore distribution and the surface acid properties were preliminarily studied, and the results showed that the hydrophilic properties and the mesopores of the molecular sieve played important roles in the enzyme immobilization. The resulting glucose electrode exhibited good reproducibility and responded rapidly to glucose in the linear range from 1.0 × 10 ^{- 5} to 5.0 × 10 ^{- 3} M for optimum analytical performance.